In wireless communication systems, a high throughput and data bandwidth can be achieved using a high-order modulation coding scheme (MCS) with good channel conditions. The MCS has to be degraded as the channel conditions deteriorate, otherwise a receiver may not properly demodulate. For example, the receiver may experience continuous errors and request re-transmission, and thus the throughput can become extremely low. Therefore, an appropriate MCS needs to be selected based upon changes in channel conditions to maximally utilize the communication resources. An inappropriate MCS may otherwise lead to a waste of the communication resources.
While in wireless communication control, especially in the communications in industrial scientific medical (ISM) unlicensed frequency bands, frequency resources can be extremely crowded as various types of devices perform wireless data transmissions in these frequency bands. As a result, a large amount of burst and unpredictable interfering signals can be generated, causing an inaccurate prediction of channel state and signal-to-interference-plus-noise ratio (SINR).
With conventional adaptive modulation coding (AMC) methods, a MCS is adjusted only based upon SINR information with a delay. In the ISM unlicensed frequency bands having significant burst interference, especially in communication systems having guaranteed ultra-low delay and restricted number of re-transmissions, conventional AMC methods may not respond quickly and may decrease the throughput and cause data errors.